Soundproof ball mill



Feb. 18, 1930. J. E. KENNEDY Y, SOUNDPROOF BALL MILL Filed Nov. 15, 1927 INVENTOR.

A TTORNE Patented Feb.-v` 18, A1930V .UNITED STATES PATENT OFFICE IOSEPIEI E. KENNEDY, OF NEW YORK, N. Y.

soumirfaoor BALL MILL Application iled November 1.5, 1927. Serial No. 233,408.

My invention relates to sound absorbers and refers more particularly to the method absorption means.

. It is well lmown in the art that coverings have been used for attempting to silence the excessive noises of certain types of machinery but none of them contemplate the use of the specific combination of elements nor the4 method of employingthe same utilized'in this particular invention.

It is also well known that attempts have been made to silence machinery but without success and the herein disclosed method of silencing machinery by absorbing the sound is'in successful operation and new and novel over the art. v

This method is shown applied to an air swept tube mill, for the sake of illustration only, as it is obvious that the same basic principle could be applied to lalmost any noisy device with equally. as good results as are obtained in this particular application.

My invention consists of the novel construction, arrangement of parts and method of application hereinafter referred to and 'described, claimed and substantially as illustratedin the accompanying drawings, Wherev in y similar numerals refer to like parts throughout'the several views, in which:

Figure 1, is an elevation, partly in section,

' of an air swept tube mill to which the sound absorber is applied.

Figure 2,'is an enlarged cross section of Figure 1, taken onrlines 2-2 of Figure 1.

In Figure 1, the air swept tube mill 1, is

comprised of a cylinder 2, held rotatable' in` and the product passes out of the mill through the pipe 8. 'l

The cylinder 2, carrying the pulverizing balls 9, is revolved by means of a gear 10, which meshes into a pinion 11, carried by the shaft 12, in the bearings 13 and 14, one end of this shaft 12, being provided with a coupling 15, which is attached to the shaft 16, of the motor 17, and the whole apparatus is supported on the base 18.

' To deaden or absorb the sound caused by the operation of this particular'device, 4as shown, thecylinder 2, comprises a metal shell 19, inside of which is a layer of cork 20, and a lining 21.

On the outside of this shell 19, are five different layers of superimposed materials, first, a layer of cellular material 22, preferably of felt, split at 23 and 24, second, a layer of solid material 25, third, a layer of cellular material 26, preferably of felt, fourth, a layer of solid material 29, and fifth, a'layeriof fabric 30, joined together at 31, which may be coated with paint or similar material to suit requirements.

Thus it is clearly shown that there are two different and distinct cellular bodies separated by a substantially solid body and each of the cellular bodies provides an independent group of dead air spaces Whose function is to absorb the sound waves by neutralizing each others vibrations. i

- Having thus .described the preferred embodiment of my' invention, I do not wish to limit myselfhtg the exact arrangement of parts or to the application to this specific type of mechanism, as modifications may be made in the arrangement of the parts and in the application to numerous other mechanisms Without departing from the spirit of the invention or scope of the claims. A

I claim 1. A machine for the reduction of materials, with a casing, and lining, having sound producing devices therein, provided with a plurality of layers of porous sound neutralizing material having varying acoustic insulating cells therein, between the casing and the lining. l

v2. A machine for the reduction of materials, providedwith fa casing, having sound.

' producing devices therein, saidcasing provided ,wth'a cover comprised of' a plurality of porous sound neutralizing materials,

having varying acoustio insulating cellsA Y therein,

8. In combinationwith a revolving drum,

of a mill, for. the reduction of materials, con-v taining sound producing means', ai-layer of sound neutralizing material thereupon, having a suitable percentage of porosityyand,

another layer of sound'neutralizingmaterial thereupon having ,a lesser percentage ofporosity..

4. In combination with a revolving drum, of a mill, for the 'reduction of materials, conf taining sound producing'devicega layer of sound neutralizing material having a suit# vable.percentage Qi' porosity mounted there'- on, and a layer of sound neutralizing mate-- rial having a lesser percentage of porosity mounted thereupon and an outside cover.

layer 'of sound deadenin 5. The combination 'with the revolving drum of a 4mill for the reduction of materials containing sound producing devices,- of a of and, neutralizing materials having a suitahle percentage' of porosity mounted thereupon, and -a layer of sound deadening and neutralizing materials having la lesser percentage 'of porosity mountedthereupon andan outside cover of fibrous material.

6. The. combination with the revolving l drum of-a mill'for thereductionof materials' having sound producingdevices therein, of a -layer of sound deadenin'dand neutralizing vmaterials having a suitabble percentagev of porosity thereupon, a layer of lsound deademnof and neutralizinv materials havino` a t) v C h lesser percentage of'porosity thereupon and an out-side cover of librousmaterial hav-4 ing its pores sealed. A

Signed at New York,.in the. county and State of New 4York, this 14th day of November, 1927. I I v .y JOSEPH bEL KENNEDY. 

